Apple II reference manual from Apple Computer, 10260 Brandley Drive, Cupertino, CA 95014. Contents: Getting Started with your Apple II, Apple II Integer BASIC, Apple II Firmware, Apple II Hardware. Includes schematics and hardware maps.
From a 2000 interview with Chris Espinosa conducted for the Stanford Library:
"I was working for Jef Raskin, who with Brian Howard wrote the original Integer BASIC manual, when I went off to Berkeley in 1978. When I left, Jef gave me a task. He wanted to keep me on staff, but knew that I wasn't going to be able to work the hours that I had been previously. So he gave me a long-term task: he gave me what Mike Scott had assembled as the mini-manual for the Apple II, which was basically the product of a series of nightly forays into people's desk drawers for anything typed-- or handwritten, in a few cases-- that smacked of technical material, that he periodically sent with Sherry Livingston down to the Quick Print place to print, collate and assemble, and put into binder covers with clear plastic and wraparound spine and three-hole punch.
That was what was dropped in with every Apple II. That was the mini-manual. That was Apple's documentation. None of it was written consciously for an audience, and Jef said, "We need a technical manual for the Apple II." Actually, there was the mini-manual, and there was the "red book," which was essentially the same material in a red binding. Jef gave me a copy of the red book and said, "I want you to write a real manual out of this." So I went to Berkeley with this charge, and worked 20-30 hours a week in my freshman year in college, and I came back at the end of the term with a 220 pages of camera-ready output from the Berkeley UNIX system. I had taught myself TROC, I had taught myself typesetting, I had written a 200+ page manual, and that was Apple's first published technical manual for the Apple II. I still don't know how I did it, and I managed to pass my classes, too. That year."